The present invention relates to a remote control toy car and, more particularly, to a dual-gearshift position transmission mechanism for remote control toy car, which provides two transmission modes, has a compact structure, and is inexpensive to manufacture.
In a regular gasoline engine remote control toy car, a transmission mechanism is used to transmit the driving power of the engine to the front wheel system and the rear wheel system. The transmission mechanism of conventional gasoline engine remote control toy cars provides only one transmission mode, it is less efficient to accelerate the speed, and the torsion cannot be increased during low speed. In order to eliminate these problems, dual-gearshift position transmission mechanisms are developed. However, these prior art dual-gearshift position transmission mechanisms are commonly heavy, complicated, and expensive. Furthermore, the parts of these high-precision dual-gearshift position transmission mechanisms wear quickly with use.
The present invention has been accomplished to provide a dual-gearshift position transmission mechanism, which eliminates the aforesaid drawbacks. It is one object of the present invention to provide a dual-gearshift position transmission mechanism, which provides to transmission modes to improve the torsion when accelerating the speed or reducing it. It is another object of the present invention to provide a dual-gearshift position transmission mechanism, which has a simple structure. It is still another object of the present invention to provide a dual-gearshift position transmission mechanism, which requires less installation space. It is still another object of the present invention to provide a dual-gearshift position transmission mechanism, which is durable in use. It is still another object of the present invention to provide a dual-gearshift position transmission mechanism, which is inexpensive to manufacture. To achieve these and other objects of the present invention. the dual-gearshift position transmission mechanism comprises an output shaft, a first transmission gear mounted on the output shaft, the first transmission gear having a protruded block in a recessed front side thereof, a second transmission gear mounted on the output shaft, a two-way axle bearing mounted in the first transmission gear to support the output shaft in the first transmission gear, an one-way axle bearing mounted in the second transmission bear to support the output shaft in the second transmission gear, a clutch fixedly fastened to the output shaft and disposed in the recessed front side of the first transmission gear, an idle gear wheel, the idle gear wheel having a first gear meshed with the first transmission gear and a second gear meshed with the second transmission gear, a driven gear coupled to the first transmission gear, a drive gear meshed with the driven gear, and an engine controlled to rotate the drive gear, wherein when starting the engine, the drive gear is driven by the engine to rotate the driven gear and then the first transmission gear, causing the idle gear wheel to be rotated with the first transmission gear to rotate the output shaft through the second transmission gear and the one-way gear wheel; when the speed of revolution of the output shaft reaches a predetermined level, the clutch is forced by a centrifugal into engagement with the protruded block of the first transmission gear, for enabling the driving power of the engine to be directly transmitted through the drive gear, the driven gear, and the first transmission gear to the output shaft; when the speed of revolution of the output shaft drops below the predetermined level, the clutch is disengaged from the protruded block of the first transmission gear for enabling the driving power of the engine to be transmitted through the drive gear, the driven gear, the first transmission gear, the idle gear wheel, the second transmission gear, and the one-way axle bearing to the output shaft.